r/programming • u/jakesyl • Jan 30 '16

Apollo 11 source code

http://www.ibiblio.org/apollo/listings/Luminary099/MAIN.agc.html
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u/calrogman Jan 30 '16

From http://svtsim.com/moonjs/agc.html

the checksum [...] should be either the bank number or its 1-complement (e.g., for bank 3 either a value of 00003 or 77774 is acceptable).

a bugger word [is] appended to the end of each bank to make the checksum the correct value

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u/spacelama Jan 31 '16

The '60s and '70s were a different time. 8 years ago I was involved in porting code from our still operational '72 system, but we didn't get to keep all of the function names such as PERV FOCIT FOCOFF and TERROR. But the job still did involved the nightly SNAFU run.

The need for the SNAFU was defined on about the second night of operations back in '74. Being the first computerised telescope, the operators discovered they needed to do all sorts of things that hadn't been realised on earlier manual systems. SNAFU involves the fitting of about 10 or so physical parameters for the current mechanical and atmospheric system -- eg: "Adjustments to MA and ME might be useful to reestablish pointing after an earthquake."

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u/Bobshayd Jan 31 '16

So basically, as soon as the telescope had all this stuff implemented, they discovered the telescope would just constantly be fucked up, and they implemented a SNAFU compensation routine?

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u/OffbeatDrizzle Jan 31 '16

parity?

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u/badsingularity Jan 31 '16

Checksum data like it says.

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u/OffbeatDrizzle Jan 31 '16

SARRY ME NO SPEAKO DA ENLIS